org.h2.engine.SessionInterface Maven / Gradle / Ivy
/*
* Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.engine;
import java.io.Closeable;
import java.util.ArrayList;
import org.h2.command.CommandInterface;
import org.h2.message.Trace;
import org.h2.store.DataHandler;
import org.h2.value.Value;
/**
* A local or remote session. A session represents a database connection.
*/
public interface SessionInterface extends Closeable {
/**
* Get the list of the cluster servers for this session.
*
* @return A list of "ip:port" strings for the cluster servers in this
* session.
*/
ArrayList getClusterServers();
/**
* Parse a command and prepare it for execution.
*
* @param sql the SQL statement
* @param fetchSize the number of rows to fetch in one step
* @return the prepared command
*/
CommandInterface prepareCommand(String sql, int fetchSize);
/**
* Roll back pending transactions and close the session.
*/
@Override
void close();
/**
* Get the trace object
*
* @return the trace object
*/
Trace getTrace();
/**
* Check if close was called.
*
* @return if the session has been closed
*/
boolean isClosed();
/**
* Get the number of disk operations before power failure is simulated.
* This is used for testing. If not set, 0 is returned
*
* @return the number of operations, or 0
*/
int getPowerOffCount();
/**
* Set the number of disk operations before power failure is simulated.
* To disable the countdown, use 0.
*
* @param i the number of operations
*/
void setPowerOffCount(int i);
/**
* Get the data handler object.
*
* @return the data handler
*/
DataHandler getDataHandler();
/**
* Check whether this session has a pending transaction.
*
* @return true if it has
*/
boolean hasPendingTransaction();
/**
* Cancel the current or next command (called when closing a connection).
*/
void cancel();
/**
* Check if the database changed and therefore reconnecting is required.
*
* @param write if the next operation may be writing
* @return true if reconnecting is required
*/
boolean isReconnectNeeded(boolean write);
/**
* Close the connection and open a new connection.
*
* @param write if the next operation may be writing
* @return the new connection
*/
SessionInterface reconnect(boolean write);
/**
* Called after writing has ended. It needs to be called after
* isReconnectNeeded(true) returned false.
*/
void afterWriting();
/**
* Check if this session is in auto-commit mode.
*
* @return true if the session is in auto-commit mode
*/
boolean getAutoCommit();
/**
* Set the auto-commit mode. This call doesn't commit the current
* transaction.
*
* @param autoCommit the new value
*/
void setAutoCommit(boolean autoCommit);
/**
* Add a temporary LOB, which is closed when the session commits.
*
* @param v the value
*/
void addTemporaryLob(Value v);
/**
* Check if this session is remote or embedded.
*
* @return true if this session is remote
*/
boolean isRemote();
/**
* Set current schema.
*
* @param schema the schema name
*/
void setCurrentSchemaName(String schema);
/**
* Get current schema.
*
* @return the current schema name
*/
String getCurrentSchemaName();
/**
* Returns is this session supports generated keys.
*
* @return {@code true} if generated keys are supported, {@code false} if only
* {@code SCOPE_IDENTITY()} is supported
*/
boolean isSupportsGeneratedKeys();
}